This file contains the soil profile data for burned and unburned moist acidic tundra sites used to estimate C and N loss from the Anaktuvuk River Fire (2007). These sites were sampled in summer of 2008. Unburned sites were used to develop a method for estimating soil organic layer depth and plant biomass, and for determining the characteristics of unburned soil organic layers. In burned sites, we characterized residual organic soils and used biometric measurements of tussocks to reconstruct pre-fire soil organic layer depth.
Data Set Results
Soil aggregate size distribution, aggregate carbon and nitrogen, and light fraction carbon were determined for mineral soils in moist acidic tundra. Soil was sampled in control, and N+P plots of the Arctic LTER Moist Acidic Tundra plots established in 1989 and 2006.
The data set includes 15N and 13C for plant litter, soil, plants and fungal fruiting bodies (mycorrhizae), percent C (soil organic matter and percent N from samples collected in three separate trips (1990, 2004, 2007) along the transect of the Dalton Highway (AK) extending from the Yukon River on the south to Prudhoe Bay on the north.
The (ARCSSTK) did extensive research during 2009-2011 field seasons in Arctic Alaska. The objective of this data set was to measure the quantity and biodegradability of DOC from headwater streams and rivers across three geographic regions and across four natural ‘treatments’ (reference; thermokarst-; burned-, and thermokarst + burned-impacted streams) to evaluate which factors most strongly influence DOC quantity and biodegradablity at a watershed scale.
The (ARCSSTK) did extensive research during 2009-2011 field seasons in Arctic Alaska. The objective of this data set was to measure the quantity and biodegradability of DOC from headwater streams and rivers across three geographic regions and across four natural ‘treatments’ (reference; thermokarst-; burned-, and thermokarst + burned-impacted streams) to evaluate which factors most strongly influence DOC quantity and biodegradablity at a watershed scale. This table provides physical site characteristics for the locations sampled for stream water biodegradability.
Soil temperature from three locations on the eastern side of the Toolik River where by snow fences were established as part of IPY. This is a study of how soil temperatures at 10 cm and soil moisture change across the summer at our IPY snow fence site .
The Changing Seasonality of Arctic Stream Systems (CSASN) was active from 2010 to 2012. The CSASN goal was to quantify the relative influences of through flow, lateral inputs, and hyporheic regeneration on the seasonal fluxes C, N, and P in an arctic river network, and to determine how these influences might shift under seasonal conditions that are likely to be substantially different in the future. Point transects were done throughout the sampling season to determine different substrate and cover types on the stream bottom.
A spectrophotometer was used to scan the canopy vegetation at four sites along Imnavait Creek in the Kuparuk Watershed near Toolik Lake LTER, Alaska. The resulting reflectance spectra were used to calculate average vegetation indices for each site and collection day.
Extractable NH4-N and NO3-N (2 N KCl), PO4-P
(0.025 N HCl) and pH (0.01 M CaCl2) were measured on soils from a
transect along the Dalton road. Sites are Gus Shaver flowering sites and
Arctic LTER sites.
Vegetation indices calculated from reflectance spectra collected at Arctic LTER experimental plots at Toolik Lake, Alaska during the 2007-2019 growing seasons.
A spectrophotometer was used to scan the canopy vegetation of ITEX harvest plots. The resulting reflectance spectra were used to calculate several vegetation indices of interest (NDVI, EVI, EVI2, PRI, WBI, Chlorophyll Index). Average values of these vegetation indices for each ITEX harvest plot are presented here. These plots also had biomass harvests performed and were analyzed for leaf area and nitrogen content (see 2003-2009gsharvest.csv, 2003-2009gsharvestLAI-N.csv).
Inorganic Nitrogen and phosphorus were analyzed on snow samples taken from two snow pits near the long-term acrtic LTER mesic acidic tussock experimental plots. The snow layers in each pit were described and sampled separtely with the help of Matthrew Sturm.
This database contains soil and permafrost stratigraphy associated with thermokarst features near Toolik Lake and the Noatak River collected by Torre Jorgenson and Andrew Balser during summers 2009-2011. The Access Database has main data tables (tbl_) for site (environmental), soil stratigraphy, soil physical data, soil chemical data, soil isotopes (ground ice), soil radiocarbon dates, topography and bathymetry, and vegetation cover.
Decadal file describing the physical lake parameters recorded at various lakes near Toolik Research Station during summers from 1975 to 1989. Depth profiles at the sites of physical measures were collected in situ. Values measured included temperature, conductivity, pH, dissolved oxygen, Chlorophyll A, Secchi disk depth and PAR. Note that some sample depths also have additional parameters measured and available in separate files for water chemistry and primary production.
Average conductivity of the epilimnion (0-3m of water depth) found in Toolik Lake during the month of July.
Decadal file describing the physical/chemical values recorded at various lakes near Toolik Research Station during summers from 2000 to 2009. Sample site descriptors include site, date, time, depth. Depth profiles of physical measures collected in situ with Hydrolab Datasonde in the field include temperature, conductivity, pH, dissolved oxygen in both percent saturation and mg/l, SCUFA chlorophyll-a values in both volts and µg/l, and PAR.
Decadal file describing the physical/chemical values recorded at various lakes near Toolik Research Station during summers from 1990 to 1999. Sample site descriptors include site, date, time, depth. Depth profiles of physical measures collected in situ with Hydrolab Datasonde in the field include temperature, conductivity, pH, dissolved oxygen in both percent saturation and mg/l, SCUFA chlorophyll-a values in both volts and µg/l, and PAR.
Decadal file describing the chlorophyll a and primary production in various lakes near Toolik Research Station (68 38'N, 149 36'W) during summers from 1983 to 1989. Sample site descriptors include an assigned number (sortchem), site, date of analysis (incubation), time, depth and rates of primary production. The amount of chlorophyll a and pheophytin were also measured.
Decadal file describing the physical/chemical values recorded at various lakes near Toolik Research Station. Sample site descriptors include site, date, time, depth. Depth profiles of physical measures collected in situ with Hydrolab Datasonde in the field include temperature, conductivity, pH, dissolved oxygen in both percent saturation and mg/l, SCUFA chlorophyll-a values in both volts and µg/l, and PAR.
Decadal file describing the chlorophyll a and primary production in various lakes near Toolik Research Station (68 38'N, 149 36'W) during summers from 2010 to 2020. Sample site descriptors include an assigned number (sortchem), site, date of analysis (incubation), time, depth and rates of primary production. The amount of chlorophyll a and pheophytin were also measured.
Decadal file describing the chlorophyll a and primary production in various lakes near Toolik Research Station (68 38'N, 149 36'W) during summers from 1990 to 1999. Sample site descriptors include an assigned number (sortchem), site, date of analysis (incubation), time, depth and rates of primary production. The amount of chlorophyll a and pheophytin were also measured.
A spectrophotometer was used to scan the canopy vegetation of ITEX flux plots. The resulting reflectance spectra were used to calculate several vegetation indices of interest (NDVI, EVI, EVI2, PRI, WBI, Chlorophyll Index). Average values of these vegetation indices for each ITEX flux plot are presented here.
Decadal file describing the chlorophyll a and primary production in various lakes near Toolik Research Station (68 38'N, 149 36'W) during summers from 2000 to 2009. Sample site descriptors include an assigned number (sortchem), site, date of analysis (incubation), time, depth and rates of primary production. The amount of chlorophyll a and pheophytin were also measured.
Soil stratification was determined by measuring the vertical thickness of three main strata (surface acrotelm, mid-depth catotelm, and bottom mineral soil) found in organic-rich or peat soils in the Toolik Lake region, North Slope of Alaska. Additional data for each site include dominant vegetation, landscape position, glacial surface, and microtopography.
Soil cores of 5 cm diameter down to frozen
Dissolved organic carbon (DOC) was leached from permafrost soils near the Toolik Field Station in the Alaskan Arctic and then characterized for its photochemical properties. Oxygen (O2) consumed from photo-oxidation of permafrost DOC was measured as a function of sunlight wavelength, defined as the apparent quantum yield spectrum of photo-oxidation (O2 consumed per mol photon absorbed by DOC). Carbon dioxide (CO2) produced from photomineralization of permafrost DOC was measured as a function of sunlight wavelength, defined as the apparent quantum yield spectrum of photomineralization (CO2
Dissolved organic carbon (DOC) was leached from p
Dissolved organic carbon (DOC) was leached from permafrost soils near the Toolik Field Station in the Alaskan Arctic and then characterized for its photochemical properties. The photodegradation of carboxyl carbon (C) within permafrost DOC was quantified by 13C nuclear magnetic resonance (NMR).
Soils were collected from the frozen permafrost layer (greater than 60 cm below the surface) at six sites underlying tussock or wet sedge vegetation, and on three glacial surfaces on the North Slope of Alaska during the summers of 2015 and 2018. Dissolved organic carbon (DOC) was leached from each permafrost soil and the water chemistry was analyzed.
Dissolved organic carbon (DOC) was leached from permafrost soils near the Toolik Field Station in the Alaskan Arctic and then characterized for its photochemical properties. The radiocarbon (14C) and stable carbon (13C) isotopic compositions of carbon dioxide (CO2) photochemically produced from permafrost DOC were quantified.
Dissolved organic carbon (DOC) was leached from permafrost soils collected from the frozen permafrost layer at five sites underlying moist acidic tussock or wet sedge vegetation, and on three glacial surfaces on the North Slope of Alaska during summer 2018.
Dissolved organic carbon (DOC) was leached from permafrost soils near the Toolik Field Station in the Alaskan Arctic and then characterized for its photochemical properties. The apparent quantum yield of photomineralization (photochemical carbon dioxide, CO2, production) of permafrost DOC was quantified at 309 nm.